1. Field of the Invention
The present invention relates to a wave length aligning apparatus using an arrayed waveguide grating (AWG), and particularly, to a wavelength aligning apparatus using an arrayed waveguide grating which is capable of aligning optical sources using a transmission characteristic of an arrayed waveguide grating in a wave length alignment method which is capable of maintaining a compatibility between multiple channel optical transmission systems by equally and differently aligning wavelengths in order to prevent a crosstalk caused due to an optical fiber four wave mixing effect in a wavelength splitting multiple channel optical transmission system.
2. Description of the Conventional Art
Conventionally, an optical frequency (or wavelength) splitting multiple transmission method in which the channels having different optical frequencies (or wavelengths) are combined and transmitted through one optical fiber transmission line is directed to extracting a desired channel wavelength using an optical filter which is capable of recognizing a wavelength by the channel and an optical fiber grating in a side where a predetermined signal is received by an optical signal transmission technique which is capable of expanding a transmission capacity.
There are known two methods for binding the wavelengths of signal channels in the conventional art.
The first method is directed to differently aligning channel intervals in order to reduce noise due to a four wave mixing (FWM) effect between channels.
The second method is directed to setting the channels at even intervals for enabling a compatibility of the system and simplifying the construction thereof.
In the first method, since it is difficult to obtain a desired effect of channel intervals, a predetermined technique is additionally needed for obtaining a compatibility between systems.
In the second method, if an intensity of light is strong, and the phases are matched, the performance of the system is decreased due to noise which is caused by the four wave mixing effects.
Here, the four wave mixing effect denotes that a new wavelength light corresponding to the difference between two wavelengths is generated when a light intensity is increased by a non-linear characteristic of an optical fiber, and the phases are matched at the time of transmitting various wavelengths using one optical fiber.
If a newly generated wavelength light is matched with the light having a predetermined wave length value, thus causing a distortion of a signal wave form, the above-described four wave mixing effects are increased when the wavelength intervals between channels are equivalently spaced-apart.